The invention relates to an electric lamp comprising:
a lamp vessel closed in a vacuumtight manner and having a wall enclosing the interior space; PA0 an electric element arranged in the interior space of the lamp vessel; and PA0 a metal layer provided on a substrate.
Such an electric lamp is known from DE 3040812-A1.
The known lamp is designed for use as a vehicle headlamp and is for this purpose accommodated in a reflector which has a light emission window. A non-translucent shield is placed over part of the lamp in order to prevent that light originating from the electric element will emerge directly through the light emission window of the reflector during lamp operation. This shield is partly surrounded by a hollow cylinder. The metal layer is present on the wall of the hollow cylinder which also partly surrounds the lamp vessel. Among the favorable properties of the metal layer is that it gives the lamp a colorless appearance in the switched-off state.
A disadvantage of this separate, non-translucent shield, the separate hollow cylinder, and the metal layer provided thereon, is that they lead to undesirable reflections of the light generated in the electric element. A comparatively large fraction of the light issues to the exterior through the light emission window at unfavorable angles during lamp operation as a result of this, which involves a serious risk of glare for other road users.
A further disadvantage is that the lamp has a comparatively heavy, complicated construction which is difficult to assemble owing to the many separate components.